The invention pertains to a method for making a laminate or laminated panel comprising at least the following steps:
placing a first metal sheet on a form tool or a substrate,
placing an adhesive layer on top of the first metal sheet,
placing a second metal sheet on top of the adhesive layer such that at least one of the metal sheets overlaps at least one edge of the other metal sheet, applying heat and pressure to the thus obtained stack (i.e. mainly or solely to the side of the stack facing away from the form tool or the substrate).
Such a method is known from, for instance, U.S. Pat. No. 5,429,326, which is directed to a laminated body panel for aircraft applications. The panel comprises at least two metal layers with an adhesive layer provided therebetween. The metal layers are composed of two or more sheets or sections which are generally coplanar and separated by a so-called splice or splice line. It is described how a splice in a first metal layer is parallel to but laterally spaced from the splice in a second, adjacent metal layer. By using this staggered stacking the maximum width of the laminate is no longer restricted to the width of the metal sheets or sections, which width is limited to approximately 165 cm by present manufacturing technology.
A further advantage resides in that the spliced laminates of U.S. Pat. No. 5,429,326 surprisingly have an increased residual strength (i.e., strength after the laminate has been damaged by, for instance, impact) for loads parallel to the splices when compared with unspliced laminates.
However, it is desirable (and in many cases prescribed by safety regulations) to cover (part on the splice with a so-called doubler to prevent exposure of the splice to environmental conditions and to increase the tensile strength (for loads in a direction transverse to the splice lines) of the laminate at and near the splice in the metal layers.